Piston for single-acting engines



Jan. 13, 1931'. w. TOBLER PISTON FOR SINGLE ACTING `ENGINES y Filed June 11, 1929 lll INM-:NTU Pv' Patented Jan. 1 3, 1931 UNITED `STATES WERNER TOBLER, OF WINTERTHUR, SWITZERLAND,

Ass-IGNoB. To THE FIRM oF SUL- zER FRERES SOCIETE ANONYME, or WINTERTHUR, svvx'r'znlmnNnA PISTON FOR SINGLE-ACTING ENGINES application mea :une i1, 192s, serial No.

This invention relates to pistons for single-acting engines of the kind having a gudgeon pin mounted within the body of the piston and directly engaged by the connecting rod which is .not provided with a crosshead. v The object of the invention is to provide a piston of this type which can be readily dismantled and in which the gudgeon pin does not in any way interfere with the piston skirt.

According to this invention the gudgeon pin is shorter than the internal diameter of the piston skirt and that surface of the central portion of the pin which lies between the forked arms of the connecting rod and is adjacent to the piston head is detachably secured to the body of the piston. Preferably the surface of the udgeon pin opposite to the cylinder head is formed as a cylindrical bearing for the connecting rod. In this way not only can the piston be more readily dismantled but the skirt of the piston is entirely free from the gudgeon pin or any action thereof. i

, The part of the gudgeon pin which ist attached to the piston is preferably secured to the piston head by a conical r1b or web and in addition approximately parallel reinforcing ribs connectin the gudgeon pin support to the skirt o the piston may beprovided. The gudgeon pin is detachablyv secured by studs or bolts which are accessible after the cylinder head has been" removed and the pin preferably fits into a recess in the piston body having flat Surfaces which can be machined through the openend of the piston skirt without havin to interfere with thc wall or cylindrical surfaces of the piston.

One construction of piston according to this invention is illustrated by way of example in the accompanying drawings, in

which A Figure 1 is a section on the line I-I of Figure 2, Figure 2 is a section on the line II-II of Figure 1,

Figure 3 is a cross-section IIT-*III of Figure 1, and' FigureA is a vertical section through the ony the line 369,953, and in Switzerland Iuly 2, 1928.

upper end of the lconnecting rod on the line IV-IV of Figure l.

In the construction illustrated the piston comprises a body portion a having a head b to which the skirt c is detachably secured in the known manner. The connecting rod d directly engages a gudgeon' pin e without the use f a crosshead the ends of the pin e, which do not engage theskirt in any way, supporting` the bearings f formed in the forked end of the connecting rod d. That surface of the central portion of the gudgeon Apin which lies between the forked arms of the connecting rod and is adjacent to the piston head is detachably secured toA the piston and the opposite surface of `the central portion of the pin forms a cylindrical bearing -for the connecting rod. Thus the forces to be transmitted by the connecting rod to the piston are substantially at right angles to the length of the gudgeon pin and bending stresses are almost entirely avoided. The central portion g of the piston body to which the gudgeon pin is secured is directly supported on the piston head by means of a conical web L and in addition substantially parallel ribs z' connect the central portion of the body to the skirt .of the piston forming a box-like structure as clearly shown in Figure 3.

The gudgeon pin is detachably connected to the body of the piston by studs 711 which are accessible from the upper end of the pisf 'ton after the piston head has been detached'.

Thus by 'releasing the studs f the piston can be withdrawn through the upper end of the g cylinder without dismantling the connecting ,l

rod bearings and similarly the connecting rod-can be uncoupled from the piston without removing the latter from its cylinder. The central portion of the gudgeon pin is provided with flat surfaces which fit into a corresponding recess formed in the central l portion g of the piston body and these surfaces can be machined or otherwise worked without it being necessary to pierce the skirt or otherwise interfere with the continuity of the cylindrical wall of the piston.

Such a piston is articularly for use with internpl applicable a combustion yengines since, owing to the freedom from any aperturesin the skirt, no leakage can take place past the gudgeon' pin which prevents vany discharge of lubricant into the exhaust such as usuallyoccurs with pistons `of known construction.

I claim z 1. A piston having a head and a skirt, a connecting rod therefor, said connecting rod having a forked upper end, a gudgeon pin journaled at each end in said fork, said gudgeon pin having a portion between the Journals which is rigidly fixed to the bottom of the piston and asurface bearing on the stay of said fork, whereby said bearing surface as well as the bearing surfaces in the journals takes up the forces on the piston so that the forces on the piston are transmitted to the connecting rod without causing any bending stresses in the gudgeon pin.

2. In a piston for single-acting engines in combination a piston having a head and a skirt, a connecting rod, a forked end provided on said connecting rod, a gudgeon pin engaged in said forked end and of less length than the internal diameter of said piston skirt, means for` detachably connecting the central portion of said gudgeon pin to said piston, and a conical web for directly supporting the portion of said pistion to which said gudgeon pin issecured.

i -MS 3. In a piston for single-acting engines in combination a piston having a head and a Skirt, a connecting rod, a forked end prosignature.

' WERNER TOBLER.

vided on said connecting rod, a gudgeon pinv engaged in said forked end and of less length than the internal diameter of said piston skirt, means for detachably connecting the central portion of said gudgeon pin to said piston, a conical web and additional webs between the housing of said gudgeon pin and said skirt of'said piston i for directly supporting the portion of said pistion to which said gudgeon pinis secured..

4. In a piston for single-acting engines in combination, a piston having a head and a skirt, a connecting rod, a-forked end providedon said connecting rod, a gudgeon pin cn gaged in said forked end and of less length than the internal diameter of said piston skirt and means for detachably connecting the cent-'ral portion of said gudgeon pin to said piston, said means being accessible from the cover end of said cylinder.

5. In a piston for single-acting engines in combination, a piston having a head and a vskirt, a connecting rod, a forked end provided on said connecting rod, a gudgeon pin engaged in said forked end and of lessI length than the internal diameter of said piston skirt, means for detachably connecting the central portion of said gudgeon pin to said piston, said means being accessible from the cover end of said cylinder, said gudgeon pin being provided with a surface 

